1. Field of the Invention
The invention relates to an apparatus for coating objects by means of vapor deposition. Coating process chambers are connected to a microwave device.
2. Description of Related Art
Examples of suitable objects include optical objects, such as for example reflectors which are to form part of lamps, but also bottles or vials for use in the pharmaceutical or chemical industry. However, these are merely examples of a wide range of practical applications.
DE 689 26 923 T2 has disclosed a microwave ion source in which plasma chambers having a plurality of coaxial lines are connected to a coaxial line of a microwave generator. The plasma chambers are in this case in communication with one another, and consequently the electromagnetic fields in the individual chambers have an influence on one another. An ion beam emerges from each plasma chamber of the microwave ion source, with a large-area ion beam being generated by the interaction of the plasma chambers.
DE 195 03 205 C1 relates to an apparatus for generating plasma in a reduced-pressure vessel with the aid of alternating electromagnetic fields, with a conductor in rod form being guided through the reduced-pressure vessel inside a tube made from insulating material.
DE 41 36 297 A1 describes an apparatus for the local generation of plasma by means of microwave excitation. In this case, a tube made from insulating material, which acts as a boundary with respect to the reduced-pressure region and inside which there is an inner conductor made from metal, is provided in a treatment chamber; the microwaves from a microwave source are introduced into the inner conductor. This known apparatus makes use of the effect whereby a type of coaxial line which transmits the microwave is formed at the outer wall of the carrying waveguide by virtue of the properties of the ionized gas.
Numerous demands are imposed on apparatuses of this type. The coating result has to satisfy the requirements for example with regard to the uniformity of the layer thickness and the reproducibility from object to object. Furthermore, the installation should have the maximum possible yield of objects per unit time. The energy consumption should be as low as possible.
These demands are not met or are not met in full by the known apparatuses.